tijie

#include <bits/stdc++.h>
using namespace std;
int main(){
	long long n,k,t,a[10000010];
	cin>>t;
	while(t--){
		cin >> n >> k;
   		for(int i = 1;i <= n;i++){
        	cin >> a[i];    
    	}
    	if(k >= 1 && k <= n){
        	cout << a[k] << endl;
    	}
		else{        
        	cout << "-1" << endl;     
    	}
	}
	return 0;
}